Synthetic aperture radar (SAR) imaging systems are widely used in urban, aerial and space reconnaissance. Usually, an aircraft or a spacecraft is provided with a SAR imaging system which transmits radar pulses and collects radar echoes corresponding to the radar pulses reflected by an object to be imaged.
Interferometric SAR techniques have also been developed for generating 3D images of a scanned object. In an example of such interferometric techniques, two optical SAR images are generated and optically combined in order to produce their interference fringes. The phase information related to the third dimension of the fringes can be extracted. The two optical images are representations of a same target area from different angles of view. Such interferometric SAR systems require the simultaneous generation of the two optical SAR images and therefore two optical SAR processors are required. In another example, two optical SAR images are superimposed on a photosensitive film. The photosensitive film is then developed and a SAR interference image is created by illuminating the developed photosensitive film. Such interferometric techniques require additional equipment, thereby increasing the overall weight and size of the SAR raw data processing system.
Therefore there is a need for an improved method and apparatus for generating a 3D image or pattern in a SAR imaging system.